What it is and what it does
The Siemens 3RK1911-4AB08 is an ECOFAST selective block used for selective switching-off in motor feeder circuits, with an integrated maintenance switch function. It carries a rated current of 8 A and provides a feedback contact via an M12 connector, so the control system knows when the block is in the maintenance-off position. This block is part of the SIRIUS ECOFAST system — a modular, pre-wired distribution architecture for motor control centres and machine feeder panels. The M12 feedback contact lets a PLC or safety relay confirm the switch state without running separate control wires back to the cabinet door.
Sourcing and lifecycle
The substance prohibitance date of 05/01/2012 indicates RoHS compliance alignment with the 2011/65/EU directive. This part meets current EU material restrictions for industrial equipment. Because it is an active-production part, sourcing is straightforward: quoted to order against an RFQ. No broker or surplus channel needed — standard lead times apply through Siemens authorised distribution.
Integration notes
The ECOFAST selective block mounts directly into the ECOFAST distribution system — a pre-assembled busbar and enclosure system for machine-level power distribution. The M12 feedback connector plugs into the system's control harness; no additional wiring to a cabinet door is required for the maintenance-off indication. Rated at 8 A, this block is sized for smaller motor feeders or control-circuit branches within an ECOFAST panel. The maintenance switch function provides a local lockable off position for safe access during servicing, with the feedback contact confirming isolation to the upstream controller.